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21.
Luminous and Ultraluminous infrared galaxies (ULIRGs) contain the most intense regions of star formation in the local universe. Because molecular gas is the fuel for current and future star formation, the physical properties and distribution of the warm, dense molecular gas are key components for understanding the processes and timescales controlling star formation in these merger and merger remnant galaxies. We present new results from a legacy project on the Submillimeter Array which is producing high resolution images of a representative sample of galaxies with log L FIR >11.4 and D<200 Mpc.  相似文献   
22.
The Solar Optical Telescope (SOT) aboard the Hinode satellite (formerly called Solar-B) consists of the Optical Telescope Assembly (OTA) and the Focal Plane Package (FPP). The OTA is a 50-cm diffraction-limited Gregorian telescope, and the FPP includes the narrowband filtergraph (NFI) and the broadband filtergraph (BFI), plus the Stokes Spectro-Polarimeter (SP). The SOT provides unprecedented high-resolution photometric and vector magnetic images of the photosphere and chromosphere with a very stable point spread function and is equipped with an image-stabilization system with performance better than 0.01 arcsec rms. Together with the other two instruments on Hinode (the X-Ray Telescope (XRT) and the EUV Imaging Spectrometer (EIS)), the SOT is poised to address many fundamental questions about solar magnetohydrodynamics. This paper provides an overview; the details of the instrument are presented in a series of companion papers. M. Otsubo is a former NAOJ staff scientist.  相似文献   
23.
The Solar Optical Telescope (SOT) aboard the Solar-B satellite (Hinode) is designed to perform high-precision photometric and polarimetric observations of the Sun in visible light spectra (388 – 668 nm) with a spatial resolution of 0.2 – 0.3 arcsec. The SOT consists of two optically separable components: the Optical Telescope Assembly (OTA), consisting of a 50-cm aperture Gregorian with a collimating lens unit and an active tip-tilt mirror, and an accompanying Focal Plane Package (FPP), housing two filtergraphs and a spectro-polarimeter. The optomechanical and optothermal performance of the OTA is crucial to attain unprecedented high-quality solar observations. We describe in detail the instrument design and expected stable diffraction-limited on-orbit performance of the OTA, the largest state-of-the-art solar telescope yet flown in space.  相似文献   
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We determined the focal mechanism solutions(FMS)of aftershocks of the 2008 Wenchuan earthquake using the waveform data recorded by the Western Sichuan movable seismic array. We further obtained the spatio-temporal variation of the stress field by inverting the stress tensors from these data. The results show that the FMSs of the small earthquakes are primarily reverse faulting with considerable number of normal and strike-slip. The proportion of reverse type earthquakes clearly increases with time, and the spatial distribution of the FMSs is closely related with local geology and the characteristics of the deep faults. The stress tensor inversion results reveal that the orientations of the maximum horizontal compressive stress(SH)shortly after the mainshock in each area are mainly in EW to NWW-SEE directions, while in the area along Xiaoyudong-to-Lixian aftershock branch it is in NE-SW direction in shallow crust. This implies that the stress field at the early stage after the Wenchuan earthquake is mainly controlled by the dynamic stress change caused by the rupture propagation, and the conspicuous factor determining the SH direction is the characteristics of the rupture plane. Temporal variations of the stress tensors show that the stress regimes at depth changed from a mixture of reverse and strike-slip faulting to pure reverse, implying that local Coulomb stress caused by the main shock is released through strike-slip faulting and gradually recovers into the background stress field. The change of stress in the shallow subsurface follows that in the deep subsurface with observable time delay.  相似文献   
27.
Structural, morphological, magnetic, and thermal properties have been investigated for a novel post-perovskite oxide CaPtO3 synthesized under high pressure. By comparing obtained structural parameters with those for known post-perovskite compounds, we argue that the chemical bond has a strong covalent character. Precise measurements of the Langevin susceptibility χ 0 = −9.6 × 10−5 emu/mol and Debye temperature θ ∼ 470 K provide a good opportunity to confirm the reliability of first-principle calculations on predicting physical properties of the Earth’s D” layer.  相似文献   
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GeoJournal - Maize is one of the potential crops can help in regional food production with self-sufficiency of foods in the drought prone areas of East Java in Indonesia. The purpose of this...  相似文献   
29.
Asia grew in the Late Permian by the collision of a number of micro-continents. Syn- to post-collisional magmatism occurred along the continental collision zones . In this study, we report two types of granitic rocks, garnet granite (Grt granite) and orthopyroxene granite (Opx granite), from the Kontum massif, central Vietnam, which is situated on the continental collision zone between the South China and Indochina cratons. These granitic rocks were formed at ca. 250 Ma when high-temperature (HT) and ultrahigh-temperature (UHT) metamorphism took place in the same zone. Based on the petrological and geochemical features compared with previously reported experimental results, garnet-bearing granite is derived from pelitic gneisses by partial melting, whereas orthopyroxene-bearing granite is produced by the partial melting of garnet-bearing mafic granulites. We inferred that a significantly high-geothermal gradient is required to produce Vietnamese granitic magmatism and related HT to UHT metamorphism. This geotherm may be attributed to upwelling mantle plume beneath the Kontum massif during the Late Permian.  相似文献   
30.
Spherical harmonic geomagnetic data analysis is a convenient technique to estimate equivalent current systems and to separate the external from the internal fields. However, there are certain cautions which need to be taken in the procedure, as demonstrated by some examples of the analyses of geomagnetic daily variations during solar active and quiet periods. Questions concerning the proper level of series truncation, problems with sharp gradients of the northward amplitude in narrow latitudinal zones, and dependence of results on which horizontal component is selected (northward, eastward or both) are discussed for the northern hemispheric equivalent current systems.  相似文献   
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